Why Twitter Ties Resemble Airline Hub Maps

Some new research throws into question things we say all the time about the Internet. The research focuses on Twitter, the service that lets many millions of people send short messages to each other from computers or cell phones. It's commonly said that social networking like this is revolutionary, that it's created new communities, even that it's obliterated geography. You can connect with people who share common interests, not just people who happen to live nearby. NPR's Shankar Vedantam is here to explode all that. Hi, Shankar.

SHANKAR VEDANTAM, BYLINE: Hi, Steve.

INSKEEP: OK. What does the research is wrong with our assumptions?

VEDANTAM: Well, so Twitter is a micro-blogging service and it allows people to follow people anywhere else in the world. Now, the conventional wisdom, as you said, is that the way we make social connections is by who we live close to, who's in our neighborhoods. The premise of Twitter, one of the premises, is that geography no longer matters, that we are bound together by common interests and not by where we live. And the second premise is that Twitter is a truly democratic medium, that you could be living in a small town in a country no one's heard of but you could have a megaphone now that is heard all over the world.

INSKEEP: And you could be a lonely protestor in Libya and say something that changes the world.

VEDANTAM: Exactly. So this new research by this sociologist called Barry Wellman at the University of Toronto, where he analyzed half a million tweets, and he tried to find out where people are tweeting from and who is following them. And he's found two things that both contradict our conventional view of what Twitter has to offer. So the first is the idea that geography no longer matters, but Wellman finds that actually isn't the case. Here he is...

BARRY WELLMAN: We found out that a lot of Twitter ties are local. People have local interests. You know, in Toronto we're worrying about subways, we're worrying about politics, we're worrying about the Toronto Maple Leafs, we're worrying about Justin Bieber, who's a local boy.

VEDANTAM: So now, the second premise is that Twitter is a truly democratic medium, and this is, of course, democratic with a small D, that it truly doesn't matter, we've exploded national hierarchies, it doesn't matter where you live, in a, you know, mega-world-class city or in a small town somewhere. And Wellman again finds that isn't the case, that if you in certain cities, you're much more likely to be followed by people in other similar cities than if you're living in a small town. Here he is again...

WELLMAN: Los Angeles is more likely to be connected to Toronto than St. Louis. And my apologies to St. Louis, but Torontonians rarely go to there. Tweets - to use the Twitter term - are more likely to be connected to each other between those localities than not.

VEDANTAM: So I don't know if that makes sense to you, Steve, but if you take a look at this map that I've printed out for you, what do you think it shows you?

INSKEEP: Well, what I'm looking at here is something that looks like the map that you see in the back of an airline magazine that shows all the routes going from the various hubs across the country, around the world, and a bunch of lines drawn between cities.

VEDANTAM: Exactly. So these are airline connections, looking at all the hubs that are connected to one another. And what Wellman has found in Toronto is that the airline connections between your city and the rest of the world predict where your Twitter followers are going to be. So if your Twitter followers are an airline flight away, they're much more likely to have Twitter connections to you than if they're not accessible by a plane.

INSKEEP: Suggesting what? That Twitter connections are following the connections that we already have in the real world?

VEDANTAM: Exactly. So that the real world powerfully predicts what kind of connections we have in the virtual world. So if you are living in New York, you're much more likely to have followers in London than you are likely to have followers in a small town in the United States.

INSKEEP: Because New York and London are already connected in many powerful ways.

VEDANTAM: Exactly. So airline connections in many ways are predicting that these two cities have common interests, that there's a lot of trade maybe between them. There's a lot of people who have similar kinds of professions or similar interests who live in those kinds of cities. But this really calls into question the notion that Twitter is a truly democratic medium.

INSKEEP: Granting that Twitter in some ways is following our real-world connections, does it in some way intensify them and make connections possible in ways it wouldn't have been before?

VEDANTAM: Yeah. It is the case that you really can follow people anywhere in the world. But what isn't true is this vision that Twitter is a truly flat medium. You know, Tom Freedman wrote this book saying the world is flat, and what Wellman is basically finding is that, no, the world isn't flat. The world is actually very lumpy. And if you're living in one of those big lumps, you're much more likely to be connected to people in one of the other lumps than if you're living in the flat part of the world.

INSKEEP: Well, Shankar Vedantam, we're glad you're in our lump here.

VEDANTAM: Thanks so much, Steve.

INSKEEP: NPR's Shankar Vedantam. He regularly joins us to discuss interesting new research. You can follow him on Twitter, by the way, @HiddenBrain. And you can follow this program @MorningEdition and @NPRInskeep. Transcript provided by NPR, Copyright NPR.